The town was merged with the city of Montreal for several years, but its residents elected to reinstate the city as a separate entity in 2006.

In 2001, the official Commission de toponymie du Québec ruled that the correct way to write the city's name was Dollard-Des Ormeaux (one hyphen, one space, all title caps). However, this was not widely accepted and is rarely used in practice. In particular, , the city's own website does not use this way of writing the city's name.

Early history

On July 29, 1924, Dollard-des-Ormeaux detached from the Parish of Ste-Geneviève and became a separate municipality in response to a tax imposed by the Parish road improvements on Gouin Boulevard. Its first mayor was Hormidas Meloche.

Later history

The City of Dollard-des-Ormeaux obtained a new charter and was incorporated as a city on February 4, 1960.

Dollard-des-Ormeaux was originally a bedroom community in the early 1960s. In 1961, there were 1,800 residents, and there were 25,000 in 1971.

One of its original main axes, Anselme-Lavigne Street in the Westpark neighbourhood, is named for a farmer who sold his land to the Belcourt Construction Company. Many of the streets in the Sunnydale neighbourhood, including "Sunshine" and "Hyman", are named for members in the prominent Zunenshine family who owned Belcourt. The community is a mixture of residential and commercial properties. Des Sources and St-Jean Boulevards are its main commercial arteries.

The Town Hall was located in a house on Des Sources Boulevard in the early 1960s, and was moved to an 1806 French-Canadian farmhouse in 1964.

During Canada's centennial anniversary in 1967, the town decided to create a "Centennial Park," featuring a man-made lake and hills. It was suggested to use this project for a reservoir for stormwater drainage, as the City was faced with the need to expand surface drainage pipes. However the project ran into problems and became a local scandal and a major drain on resources. It was finally completed in the 1970s, albeit overdue and overbudget.